Barrier or arc-deflector for dynamo-electric machines or the like



1.]. LINEBAUGH.

BARRIER 0R ARC DEFLECTOR FOR DYNAMO ELECTRIC MACHINES OR THE LIKE.

APPLICATION FILED MAR- 6. 191a.

1,33 1 ,936. Patented Feb. 24, i920.

Inventor:

Jesse J. Line augh, W

Hi5 flttorneg.

JESSE J. LINEBAUGH,

OF SCHENECTADY, NEW YORK, ASS IGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

BARRIER OR ABC-DEFLECTOR FOR DYNAMO-ELECTRIC MACHINES OR THE LIKE.

Specification of Letters Patent. I

Application filed March 6, 1918. Serial No. 220,870.

To all whom it may concern: I

Be it known that I, JESSE J. LINEBAUGH, a citizen of the United States, residing at Schenectady, inthe county of Schenectady, State of New York, have invented certain new and useful Improvements in Barriers or Arc-Deflectors for Dynamo -Electric Machines or the like, of which thefollowing is a specification. I

My invention relates to barriers or are deflectors for use on dynamo electric machines or the like provided with commutators and has for its object the prevention. of flashovers or arcing between sets of commutator brushes of such machines or between a set of commutator brushes and'parts of such machines of opposite polarity 0r ground,-upon the occurrence of heavy overloads or shortcircuits. 1 V

In accordance'withmy invention, I provide a barrier between adjacent sets of brushes consisting'of' a cooling device for breaking'up and coolingt'he are which is produced from the brushes upon the occur-.

rence of a short-circuit or a heavy overload.

The features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forminga part of this specification. .For a betterunderstanding .of my invention, reference may be had to the following description taken in connection with the accompanying drawing, in which Figure 1 is a perspective view of a dynamo electric machine provided with my invention; Fig; 2 is a sectional view of the barrier of Flg. 1; Fig. 3 is a plan view. of amodified form of my barrier, and Fig. 4 is a sectionalview of a further modification.

Like numerals of reference are used throughout the several figures 'of the 'drawinoto designate like parts.

1 In Fig. 1 of the drawing, there is shown the commutator end of a dynamo electric machine which may be either'a direct current motor or generator, or a rotary converter- '1 is the'frame of the machine, 2 is the armature provided with a commutator 3 on which sets of brushes 4 bear. Thearmag ture and commutator are mountedon a shaft 5 Wl1lClflIlS shown journaled in a bearing 6 and the direction of rotation of the armature" is; indicated by the arrow. In accordance with my invention I provide a barrier between adjacent sets of brushes' l comprising a cooling device such as a screen for breaking up and cooling'the are which is 'produced from the brushes upon the occurrence of a short-circuit or a heavy overload. In the particular embodiment of my invention illustrated, each of these barriers comprises a fine mesh metal screen 7 and a coarse mesh metal screen 8, the coarse mesh metal screen being located in front of the fine mesh metal screen having reference to the direction of rotation of the commutator 3, as clearly seen from Figs. 1 and 2 of the drawing. The wire of the coarse mesh screen8 should have suflicient thermal capacity to cooltheare down to the point where there is not enough heat left therein to burn either the coarse meshv or the fineme'sh screen. The fine mesh screen takes out substantially all the heat that is left in the are when it reaches this screen and thus puts the are out. In order to form an arc chute, or in other words, to

Patented Feb. 24, 1920.

make the arc flow upwardly from the com- 1 mutator instead of toward the armature or the bearing 6, I provide members 9, 9 of insulating material at each end of the commutator, these members extending from a set of brushes to its corresponding barrier. I have shown these members as completely encircling both ends of the commutator and spaced inwardly a slight distance from both ends so th. t the ends of the bars project beyond these members. I prefer to have these members completely encircle the commutator for mechanical reasons,but find that, so far as they are necessary to form an arc chute,they need only extend from a set'of brushes to its corresponding barrier. A con venient way of mounting the metal screens is by providing an insulating member 10 in front ofwhich both the metal screens are located having reference to the direction of rotation of the commutator, and to which the metal screens are clamped by means of bolts engaging members 11. The insulating member 10 extends completely across the commutator from member 9 to member 9", and it is supported by these members 9, 9 by means of brackets 12, 12. In order to support the metal screens and toprevent-their coming into contact. with the comn'iutato-r.

and thereby short-circuiting it, I provide members 13 of insulating material which may be fastened to the members 9, 9c and 10. These insulating members 13 are U- shaped and may be provided with grooveslet in which the screens are mounted.

A barrier constructed as described, above will diffuse and cool an are, which is produced from the brusl es upon-theoccurrence of a short circuit or a heavy overload, and will; prevent any bur-ningor damage, which would otherwise-be caused to-thebnush rigging, communtator and other parts-of a dynamo electric machine.

In the modification shown in; F 3, I have mounted the screen differently than that shown in Figs. 1 and 2,'and havexdone away with-the insulating member l0. In

the construction of this figure; a fine metal screen 7 and a coarse metal screen 8 extendsacross the commutator betweenadjacent sets of brushes and are fastened: tothe I insulating members 9 by means. of bolts and members II. V The coarse metalscreen in this constru-ctlonis also located in front of" the fine mesh metal screen. havingwefeie ence to the direction of IOtatIOIIIOf thG: com: mutator, and both these screens "are pres vented from coming into: contact Withthe commutator by an insulating. member 13'? which is" also supported bythe insulating. members 9"l0cated at each'end of the com-Ir mutator. 7

In the modification shown m Fig; 4, the fine mesh screen 7" nd the coarse meshscreen 8" are mounted substantially thesame way-as are-the screens in Fig, The endportion of the screens away from the com-' mutator, that is, the portions 7 2 of the fine mesh-screenand the portions 8 'ofthe coarsemesh screenare bent backward with refer-- ence' to the direction of rotationof the com- I,

mutatorso as to act as a barrier against-any portion of the are from the brusheswhich wouldtendto escape over the barrier ifthese portions of the screens were not inter posed into the path of" the are;

I desire it to be understood that my invention is not limited to the particular arrangement shown and described,and I aim in the appended claims to cover' alljmodifica-- tions which do not depart from the-spirit and scope of my invention.

What I claim as new-and desire to secure by Letters Patent of the United States, is=:'- 1. In combination; a commutator, sets--of brushes therefor, and barriers located-"be tween adjacentsets of brushes, eachiof said' barriers comprising a fine mesh metal screen: and acoarse mesh metal screen;

2. In combination, a commutator, sets of brushes therefor, and barriers located between ad acent sets of brushes, each of said barriers comprlsing a fine mesh-metal screen and: a. coarsejmesh metal screen, said coarse mesh, metal screen being located in front of said fine mesh metal screen having. reference to. the. direction of rotation ofsai'dcommm tator.

3. In combination, a, commutator, sets: of brushes therefor, barriers located between adjacent sets of brushes, each of said barriers comprising a metal screen,-and=membQlfS of insulating; material located at each end of the commutator, each of said members extending from a-set of brushestodts corresponding. abarrierfi 4. Incombina-tion, a-commutator, setsnof brushestherefor, bairierslocated between ad-. jacent sets of brushes,.each of said barriers comprising avfinemeshimetal screen, and a coarse mesh metal screen, said'coarse mesh metal screens beingflocated in front of said fine mesh metal screen having. reference to the-direction of'rotationof saidcommutator,

andirmembers of insulating material: located at eachendof the commutator, eachof' said members extending fromaset; of brushes to.

its -:cor-1-'espondingbarrier. I

5. In combination,: a "commutator, sets 'of-Y brushes: therefor,- and barriers located be-; tween adjacent sets'jofzbrushes, each ofsaid barriers comprising insulating :member and a metal screen supported thereby,'saidy metal screen being locatedin-vfront of said insulatingmember having reference to the direction of rotation of 'sai'dcommutator;

6. combination,- a commutator, sets-of brushes therefor, barriers' locate'd between adjacent sets of brushes, each'r-ofv said bar riers comprising an A insulating memberand V catediin frent of said insulating-member having reference to; the directiom of saidcommutator.

f rotation 8J In combination, a commutator, sets of brushes; there-for, barriers located'between adjacent sets-of brush-es, each. ofsaidbam r ers; comprising an" insulating member, a fine-mesh metal screen. and a coarser-mesh:

metal screen, said coarse mesh metal screen mutator, each of said members extending being located 1n front of said fine mesh metal from a set of brushes to lts correspondlng screen and both of said screens being 10- barrier. .10

cated in front of said insulating member In Witness whereof, I have hereunto set having reference to the direction of rotation my hand this 4th day of March, 1918.

of said commutator, and members of insulating material located at each end of the com- JESSE J. LINEBAUGH, 

